URL rewrite. How to get rewrited url?

How to get rewrited url during runtime?
E.g. I click on a link like this:
http://localhost:1062/BlogEngine/post/2008/04/olimp.aspx
but in code
Request.Url.PathAndQuery.ToString() returns me real url which look like "/BlogEngine/id=b3db3642-ab5a-4aab-8ddf-60cace4e7f09?id=b3db3642-ab5a-4aab-8ddf-60cace4e7f09"
the question is how can I get a value like "BlogEngine/post/2008/04/olimp.aspx" during runtime?